Aerosol future measurement needs

Chu et al. (1987) present results of laboratory studies of the formation of an ultrafine aerosol by converting SO- to sulfuric acid using measurement methods described by Holub and Knutson (1987) and Kulju et al. (1987). It was found that the size of the resulting activity distributions is dependent on the S02 concentration. The role of humidity is still unclear and more studies are needed, but it appears that both future theoretical models and laboratory studies will be extremely fruitful in elucidating the behavior of Po-218 from shortly after its formation until its incorporation into the existing accumulation mode aerosol. 

Our understanding of stratospheric aerosols is still far from being satisfactory. In particular, the gas-to-particle conversion processes involving SO2 oxidation and condensation nuclei formation are still poorly understood. Future research, therefore, should include in situ measurements of aerosols, trace gases and condensation nuclei involved in aerosol formation. Accompanying laboratory studies of relevant chemical processes are also needed. 

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